Figure 216. Front wheel hub structure: 1 - front axle; 2 - cuff; 3 - tapered roller bearing; 4 — hub; 5 - tapered roller bearing; 6 - adjusting washer; 7 — locking clamp bolt; 8 - locking clamp; 9 — hub cap
The replacement of the hub bearing must be carried out in the following order (according to the figure 216):
Figure 217. Bearing inner ring puller
- using a two-jaw puller, remove the inner hub bearing and seal. Remove the outer ring of the inner bearing from the hub. Figure 217 shows how to install a universal two-jaw puller;
- similarly remove the outer ring of the outer bearing from the outside of the hub;
- if necessary, unscrew the brake disc from the hub. To do this, use a hex key to unscrew the bolt from the inside, having first clamped the disk through the pads in a vice;
- check the hub flange for runout. Also check the threaded holes for mounting the wheels, bearings and bearing seats.
Bearings must be replaced if the following damage is detected:
- the tapered rollers in the outer bearing cage have dents caused by peeling off of the chrome coating on the inner ring;
- corrosion spots were found on the rollers caused by water ingress through a defective cuff;
- the outer ring of the bearing is light brown or blue in color (tarnish colors), what is caused by overheating;
- if it is necessary to replace one bearing, the other one should also be replaced. Always use bearings from the same manufacturer in pairs. When installing a used bearing, be careful not to mix up the rings and separators.
When installing bearings, proceed as follows:
- first press the outer bearing rings into the hub;
- prepare the prescribed amount of lubricant (about 50 g) for hub and bearings;
- how to lubricate inner bearing separator;
- insert the inner ring with the separator into the hub, apply grease to the end surface of the rollers. Place grease between the working and dirt-sealing edges of the cuff, then carefully press it into the hub, being careful not to damage it;
- fill the hub with the remaining grease;
- install the hub as described in previous subsection.
Article text obtained from the website mercedesman.ru